1 teaspoon chocolate syrup
1 cup ice, or as needed
4 fluid ounces eggnog
2 fluid ounces coffee-flavored liqueur (such as Kahlua®)
2 fluid ounces vodka
1/4 teaspoon ground nutmeg
1 tablespoon whipped cream, or to taste
1 pinch ground nutmeg
Swirl chocolate syrup around in a martini glass.
Fill a cocktail shaker with ice. Pour eggnog, coffee-flavored liqueur, vodka, and 1/4 teaspoon nutmeg over ice; cover and shake. Strain mixture into prepared martini glass; garnish with whipped cream and 1 pinch nutmeg.